Milk product process of manufacture



July 8, 1952 R. E. MEADE 2,602,747

MILK PRODUCT PROCESS OF' MANUFACTURE Filed July 19, 1949 I Concenra//on by EVapora/'on l Po woered Pro duc/ IN VEN TOR. /Qeg//va/d E, Meade ,4 TTOEA/EVS present invention.

Patented Juy 8, 1952 MILK rRoDUc'r mtooisssror` TUBE" Reginald E. Meade`,5Appleton, Wis., assign'or to@ Western Condensing Calif., a corporation of California Y ApplicationJulyie, 1949,seria1iv."1 05,520 'i 2 claims. (c1.- 99-5s) This invention relates generally to dried powu dered milkl products or concentrates such as are suitablefor use in bread making, and to processes for theirmanufacture.

' vSkim milk-powder has becomeafnaccepted-in i gredientjinthe preparation of brea'ddough. l, Varie ous propertie's'of the powder aiT'ectits suitability forsuch usef' One characteristic which is par. ticularly important. isvthe 'ability of the powder to absorb a .substantial andjpredetermined amount of water informing a dough mixof desiredconsistency. Good quality conventional skim milykjpowderv such asis now available on the market, and produced byprocessesdnvolvsprayv drying, aiords'a water absorption; oifsub stantially 100%. This means that in preparing, standard dough mixes including" such s 1-:ir'r'rz nilk powder, an additional amount of water can be added to the mix equal by weight totheweight of K theuskim milk solids, without detrimentally aiectingthe plasticity of the dough. .Y ji Ordinary commercial wheyssuch as obtained Afrom the manufacture of casein and in the manu# facture of cheese, contain valuable nutrients; infcluding particularly lactose and protein. -Com'- inercial whey is available in edibley formy suit` able for human consump-tio`n,` and vit isrelatively inexpensive Vcompared to skim milk. 'However prior to the present linvention it has notbeen lsuccessfully used as an ingredientzin bread making. dueparticularly to thehf'actthat'when spray dried in the same manner as skim milk, it provides a powder which-'has relativelypoor water absorption. j f It is'an objet of the,presentfinvention'to provide 1a process which will'fproduce a' product containing solids from both skim milk and whey,

and which will have substantially all of the d'e sirable propertiesv of good quality spray dried skim milk in bread making, including a substantially equivalent moisture absorptiom f Another object 'of the invention is-to provide a new' article of `manufacture,namely a powdered milk product having-solids derived from skim milk'v vand commercial-when vand which is well adapted for yuse in bread making. .i t

Additional objects and features of the'inven` tion will appear from the Afollowing description in which the preferred embodiment has been set forth in detail in conjunction with the accom-` panying drawing. .-1

Referring to the drawing, the single iigure is a ow diagram illustrating one embodiment-of the ing heat-,treatment, vacuum-evaporation 'and C ompany; San Francisco,-

vThe present process involves special condition'- ing of milk proteins derived from both skim milk and Whey, prior to conversion' of the vmaterial to a dry powder, including particularly-the conditioningof all or a substantial part of the lactalbumin present. Thespecial conditioning involves substantially increasing the mineral content` together with. heatV treatment atan elevatedternperature' It 'serves togreatly increase'the abil-- ity' offthe nal 'powdered productto 'absorb vmois-'- ture, and generally improves the material -for vuse in bread making; f

Typical commercial,skimcmilk, such as can be used in thepresent process,` is produced by ccntrifuging whole milk to remove thermajority of the-butterfat present.' It contains a substantialv amount'o'f milk protein, including both casein l ad'flact'albumin." Ihe whey used-in the present content, contains l by' adjustment of the hydrogen ion concentration blended togeiillr ,at M, and are. held n' clef at l i, andheat treatment' at vI2. -It is desirable to acidulate to provide a hydrogen ion concentraytion of the order of pI-IILO to 5.6, and this is-preferably carried out l by using a' suitable .inorganic acid,'such as a 20% sulphuric acid solution. Hydr'ofchl'oric Yacid canbeused'but it increases .the salt r(NaCl) content of Vthe material and, there* forffrequiresan adjustment in the amount'of salt employe'diwhen preparing a doughmix.

In lstep I l -the hydrogen ionconcentration'is adjusted to about pHl 6.0 to 9.0, and preferably from about 6.5 to 6.75 by the addition of a suitable neutralizer, such as sodium hydroxide, lime, soda ash, or'cream neutralizar (a proprietary product). It will be evident that addition of alkali at this point forms mineral salt by reaction with the free acid present. Heat treatment in step I2 can be over a-range of fromaboutx185 to"280 F. If vheated to the higher temperatures itis desirable toyemploy flash heating,c as by direct contact Vwith steam, and :to then reduce the pressure to atmospheric to cause flash cooling by evaporation to a temperature ofV theorder of-212F. -1 r vf The skimvfmilk is heat treatedat lI3 in the same 4manner as described above for thewh'ey. Thetwo liquid materials are then miX'ed'for duced. Thus for 240 F. the time period can be about four minutes, and for 280 F. about 2.5-

minutes.

After blending and retention at the v is subjected to concentration by evaporation at I5, to produce a concentrate which may containrv centrate is then subjected to acidulationat I'B, followed by neutralization at Il, I6 can be carried out in the same .manner as the step I0, that is by use of such inorganic acids as sulphuric and hydrochloric, introduced in the formgof a dilute solution. Sufficient acid should be added to provide 'a-v hydrogen ion concentra- 'tiener from'lpn 4.o to 5.6. ,i

vAfter kacidulation` at IGl the 'material is adiusted withrespect to' its-hydrogen ion. concentration,- by introduction of ,al suitable neutralizer; as indicated! by fstep" ITI. This: step canbe Ycarried inisubstantially' the same manner asf- ,the

Acidulation at Y 4 imparts good palatability, flavor, crust color and tenderness, body texture, loaf volume and keeping properties. In addition it has good water absorptivity which can be of the order of high quality skim milk powder used in bread making, as in the foregoing example. It has been deter `mined by laboratory tests that ibread containing my product up to thec6'%,.1evel (i.` e. 6% of the weight of flour and in the dough) has greatly 'enhanced nutritive value, particularly with respect to promoting growth. 'Lactalbumin of the product plays an important part in obtaining high absorptivity, although the absorptivity is'in part due to other milk proteins for example from to 40%v Solids.; This-@03:15'present-including casein. The proteins of my f- -produ'ct'appeartobe in peculiar denatured form, f duebothvto the added mineral content, and the step- H. f Thus44 neutralizing agents such assodium hydroxida-lime; soda ash Vor cream neutralizer 'can' beused for-"this purpose; Following neu;- tralizing at il the material is spra'yrdried at i8, to produce `the final powdered product. f

' 'The-characteristics ofv the, final lproduct `vill depend upon certain variations in the process, such las the .degree of acidulation, the extentpf neutralization; the temperature .and tin'ievperiodV offbeat treatment', and the proportionsV employed betweenfthe skim. milk and Whey. Gln-.one typical instance which can be cited-l by wayl of example, edible Whey was 'acidulatedfby additionv of 20% sulphu'ric'acid solution to pH 4.5, and was then neutralized by thefadditionof milk of lime VtopH 6:.5. This m'aterialhwas then heated to 185? F., and blended with skim milk which had Vpreyiously ,been heated-tothe same .(c'orrespondingfto about 20% solids) :after which it', wasn again acidulatedi at i6, v and rneutralized atli '1. Acidulationat l6was by addition Yofw20f7o sulphuric :acid'solution to pI-If4,5, and .neutralization-".atx'll tvasby 'addition ofrnilk of llime to adj ust. the' .hydrogen ion concentration to Y pH 618; vThe proportions involved between the skim milk and-whey were such that of the lsolids inthe final product were derived from skim milk, and the remainder from whey.

'llhedried powdered product inadeaccording to the foregoing example' possessed water absorptivity-of the order of 109%,.or inother Wordslit possessed the same water absorptvity as good quality.` skimniilk'powder. Y e Ingeneral the'pro'duct resulting from my `process is particularly well suited for usey in bread making.' It possesses all of the good properties of'present day high quality skim milk powder, together with "a higher lactose content and other valuable nutrients derived from whey. `Be'cause is generally a vless expensivev raw material than'skim 'milkmy product can be made at a' lowerdcost than skim milk powder; When'inorporated ina standard bread loaf `vthe product The V:blendedmaterialwas-:then

recurrent heat treatment, and it is this denaturing .which appears to impart good absorptivity to the nal product.

It will be evident that my processcan -be modified .in various ways. For example, if. de.- siredVamineralQsalt such vas'calcium sulphate, can be used inplace of separate additions of .acidandneutralizen However somewhat better .results .have beenf noted when. thefacid ,is .rst introduced, vvfollowedgby the 'neutralizen `."fhe heat treatment jean beapplied after acidulation at lll and,before'neutralizationat l. However vfrei-n vthestandpoint of equipment corrosionlit is more .advantageous to neutralize before heat treatment. Instead of `using separateintroduc tionsofwacid and neutralizer in the'steps i'fand `Vlg-,ilimis again .possible to .use mineral'Y salts` as previously y specified. The separate heat. treatment steps 121. and |43Y can'. be consolidated, by applying heat; treatment after the .material from the neutralizing.y operation Al I has been directly blendedryvith's'kim milk.

vnvconjunctionf with special treatmentj after concentration by evaporation at I5, ,it shouldl be noted that the'denaturing of theprotein present is also effected by heat treatment .in conjunction with spraydrying atl.- During ordinaryspray dryingv the material is momentarily heated` to temperatures kof the order of.21`72-E .,Y and `this heating` at the time of yspray drying can be, sup# plemented/by preheating to temperaturesv ofthe order of from 180 to 212913., as the )material is suppliedtothefspraydrier. -Acidulation and neutralization together, with heat treatment before concentration, followed by similar treatment after concentration, produces the desirable properties of the final 'productinf cluding the desired absorptivity. Some delnaturing takes place withrespect .toL the'whey protein in steps. li), Il and i2, andwith respect to boththe whey` and lskim milkproteinvin the heating step I 4.,` After concentrationsome further denaturing occursby Virtue of steps I6 and I1, together with heating .which occurs in conjunction with spraydrying.v AInn this connection I have found that the denaturing treatment is particularly veiective whenapplied to a concen-v trate, fand denaturing-treatment applied lbeth beforeand-` after concentration enables maximum development of moisture absorptivity in the iinal product. 1- ""This application' is a; continuation-impart y .of my copendi-ng Aapplication Serial No. 38,08,.1filed July l0, 1948,-*for Milk .Product and'. Process of Manufacture, Inow abandoned.r

when used in bread dough, acidulating raw liquid whey to a hydrogen ion concentration of the order of from pH 4.0 to 5.6, neutralizing the acidulated whey to a hydrogen ion concentration y of the order of pH 6.0 to 9.0, heating the material l to an elevated temperature Within the range of` from about 185 to 280 F., heating a quantity of Vskim milk, combining the skim milk with the hot whey and retaining the blend at an elevated temperature Within said range for a period of from 30 to 2.5 minutes, concentrating the blended material by evaporation, further acidulating the material to a hydrogen ion concentration of from pH4.0 to 5.6, neutralizing the acidulated material to a hydrogen ion concentration of the order ofpH 6.0 to 9.0, and then drying the material to dry powdered form.

2. In a process for the manufacture of a dried powdered product having high water absorptivty when used in bread dough, treating raw liquid whey by acidulating the same to a hydrogen ion concentration of the order of from pH 4.0 to 5.6, by neutralizing the acidulated whey to a hydrogen ion concentration of the order of pH 6.0 to 9.0 and by heating the material to an elevated temperature within the range of from about 185 to 280 F., combining the treated whey with a quantity of skim milk and retaining the blend at an elevated temperature within said temperature range, for a period of from 30 to 2.5 minutes, concentrating the blended material by evaporation, treating the concentrate by acidulating the Vsame to a hydrogen ion concentration of from pH 4.0 to 5.6 and by neutralizing the acidulated material to a hydrogen ion concentration of the order of pH 6.0 to 9.0, and then drying the `material to dry powdered form.

REGINALD E. REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS v Number Name Date 442,593 Rehnstrom Dec. 9, 1890 482,897 Frederiksen Sept. 20, 1892 664,318 Hall Dec. 18, 1900 1,557,181 Messmer oct. 13, 1925 1,870,270 Washburn Aug. 9, 1932 2,023,014 Flanigan et al Dec. 3, `1935 2,088,606 Peebles Aug. 3, 1937 2,181,146

Peebles et al Nov. 28, 1939 

1. IN A PROCESS FOR THE MANUFACTURE OF A DRY POWDERED PRODUCT HAVING HIGH WAT ER ABSORPTIVITY WHEN USED IN BREAD DOUGH, ACIDULATING RAW LIQUID WHEY TO A HYDROGEN ION CONCENTRATION OF THE ORDER OF FROM PH 4.0 TO 5.6, NEUTRALIZING THE ACIDUALTED WHEY TO A HYDROGEN ION CONCENTRATION OF THE ORDER OF PH 6.0 TO 9.0, HEATING THE MATERIAL TO AN ELEVATED TEMPERATURE WITHIN THE RANGE OF FROM ABOUT 185 TO 280* F., HEATING A QUANTITY OF SKIM MILK, COMBINING THE SKIM MILK WITH THE HOT WHEY AND RETAINING THE BLEND AT AN ELEVATED TEMPERATURE WITHIN SAID RANGE FOR A PERIOD OF FROM 30 TO 2.5 MINUTES, CONCENTRATING THE BLENDED MATERIAL BY EVAPORATION, FURTHER ACIDULATING THE MATERIAL TO A HYDROGEN ION CONCENTRATION OF FROM 